정방 행렬의 종류 (types of pattern in square matrices)

types of pattern in square matrices

1. Symmetric matrix (대칭 행렬)
A^T = A

2. Skew-symmetric matrix
A^T = − A

3. Orthogonal matrix
A^T = A^-1

4. Toeplitz matrix (or diagonal-constant matrix)
Any n×n matrix A of the form

is a Toeplitz matrix.
If the i,j element of A is denoted A_i,j, then we have A_i,j = A_{i − 1,j − 1}.

5. Circulant matrix
6. Hankel matrix
7. Centrosymmetric matrix
8. Hilbert matrix
9. Coxeter matrix
10. Covariance matrix

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Tridiagonal matrix
In linear algebra, a tridiagonal matrix is a matrix that is "almost" a diagonal matrix. To be exact: a tridiagonal matrix has nonzero elements only in the main diagonal, the first diagonal below this, and the first diagonal above the main diagonal.

For example, the following matrix is tridiagonal: